Transcript for Remembering Vietnam War Hero and US Sen. Jeremiah Denton

And finally tonight, 47 years ago, a grainy black and white film electrified the nation. A prison nor of war in Vietnam forced to sit with his cap tors but in Morse code, he blipgd out a secret message for the world. Jeremy Denton died today. ABC's John donvan has our person of the week. Reporter: When he walked into that room, 48 years ago, he had been sadistically beaten and starved. And now, sitting, he was about to be used for propaganda. Jeremiah Denton was a Navy in 1965, who was shot down over north Vietnam with his co-pilot. Both survived. But, given the brutality of their captors, getting out alive seemed unlikely. I found that if they would just apply one kind of pain to me, I could achieve unconsciousness. I could last. Reporter: But when north Vietnamese put him on camera, they wanted him talking about how good the treatment was, which he did. If you listen to the words -- I get adequate food and adequate clothing. Reporter: But his eyes were telling a different story -- the truth. Because, watch how, he blinks for an unusually long moment. Then again, three long blinks. And then a short, and a long and a short blink. And what that was -- go back and look again -- was Morse code. One long equals "T." Three long equals "O." Short long short --"R." And on he went, spelling the word "Torture." Bold, ingenious, it was the first confirmation U.S. Navy intelligence received that P.O.W.S were being tortured. But when Denton finally was released, near the war's end, in a large group of returning pows, the public still didn't know. Even as he was the man chosen to speak that day -- We are profoundly grateful to our commander-in-chief and to our nation for this day. God bless America. Reporter: Jeremiah Denton lost nearly eight years of his life. The good new is, the rest of it was rich and rewarding and lasted a good, long time, until today. This father of seven, grand father of 14. Great-grandfather of six -- was 89. So we choose Jeremiah Denton. John McCain said that he X exemplified the slogan, home with honor.

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